Hello Philipp, On 13/06/14 18:08, Philipp Zabel wrote: > This patch allows to use the runtime pm and generic pm domain frameworks > to completely gate power to the VPU if it is unused. This functionality > is available on i.MX6. > > Signed-off-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx> > --- > drivers/media/platform/coda.c | 65 +++++++++++++++++++++++++++++++++++++++---- > 1 file changed, 60 insertions(+), 5 deletions(-) > > diff --git a/drivers/media/platform/coda.c b/drivers/media/platform/coda.c > index 8321243..f39f693 100644 > --- a/drivers/media/platform/coda.c > +++ b/drivers/media/platform/coda.c > @@ -22,6 +22,7 @@ > #include <linux/module.h> > #include <linux/of_device.h> > #include <linux/platform_device.h> > +#include <linux/pm_runtime.h> > #include <linux/slab.h> > #include <linux/videodev2.h> > #include <linux/of.h> > @@ -2820,6 +2821,13 @@ static int coda_open(struct file *file) > ctx->reg_idx = idx; > } > > + /* Power up and upload firmware if necessary */ > + ret = pm_runtime_get_sync(&dev->plat_dev->dev); > + if (ret < 0) { > + v4l2_err(&dev->v4l2_dev, "failed to power up: %d\n", ret); > + goto err_pm_get; > + } > + > ret = clk_prepare_enable(dev->clk_per); > if (ret) > goto err_clk_per; > @@ -2889,6 +2897,8 @@ err_ctx_init: > err_clk_ahb: > clk_disable_unprepare(dev->clk_per); > err_clk_per: > + pm_runtime_put_sync(&dev->plat_dev->dev); > +err_pm_get: > v4l2_fh_del(&ctx->fh); > v4l2_fh_exit(&ctx->fh); > clear_bit(ctx->idx, &dev->instance_mask); > @@ -2930,6 +2940,7 @@ static int coda_release(struct file *file) > v4l2_ctrl_handler_free(&ctx->ctrls); > clk_disable_unprepare(dev->clk_ahb); > clk_disable_unprepare(dev->clk_per); > + pm_runtime_put_sync(&dev->plat_dev->dev); > v4l2_fh_del(&ctx->fh); > v4l2_fh_exit(&ctx->fh); > clear_bit(ctx->idx, &dev->instance_mask); > @@ -3243,7 +3254,7 @@ static int coda_hw_init(struct coda_dev *dev) > > ret = clk_prepare_enable(dev->clk_per); > if (ret) > - return ret; > + goto err_clk_per; > > ret = clk_prepare_enable(dev->clk_ahb); > if (ret) > @@ -3369,6 +3380,7 @@ static int coda_hw_init(struct coda_dev *dev) > > err_clk_ahb: > clk_disable_unprepare(dev->clk_per); > +err_clk_per: > return ret; > } > > @@ -3394,10 +3406,29 @@ static void coda_fw_callback(const struct firmware *fw, void *context) > memcpy(dev->codebuf.vaddr, fw->data, fw->size); > release_firmware(fw); > > - ret = coda_hw_init(dev); > - if (ret) { > - v4l2_err(&dev->v4l2_dev, "HW initialization failed\n"); > - return; > + if (IS_ENABLED(CONFIG_PM_RUNTIME) && pdev->dev.pm_domain) { How about using the pm_runtime_enabled() helper ? Also why do you need to be checking dev.pm_domain here and in the resume() callback ? Couldn't it be done unconditionally ? Why the driver needs to care about the PM domain existence ? > + /* > + * Enabling power temporarily will cause coda_hw_init to be > + * called via coda_runtime_resume by the pm domain. > + */ > + ret = pm_runtime_get_sync(&dev->plat_dev->dev); > + if (ret < 0) { > + v4l2_err(&dev->v4l2_dev, "failed to power on: %d\n", > + ret); > + return; > + } > + > + pm_runtime_put_sync(&dev->plat_dev->dev); > + } else { > + /* > + * If runtime pm is disabled or pm_domain is not set, > + * initialize once manually. > + */ > + ret = coda_hw_init(dev); > + if (ret < 0) { > + v4l2_err(&dev->v4l2_dev, "HW initialization failed\n"); > + return; > + } > } > > dev->vfd.fops = &coda_fops, > @@ -3635,6 +3666,8 @@ static int coda_probe(struct platform_device *pdev) > > platform_set_drvdata(pdev, dev); > > + pm_runtime_enable(&pdev->dev); > + > return coda_firmware_request(dev); > } > > @@ -3645,6 +3678,7 @@ static int coda_remove(struct platform_device *pdev) > video_unregister_device(&dev->vfd); > if (dev->m2m_dev) > v4l2_m2m_release(dev->m2m_dev); > + pm_runtime_disable(&pdev->dev); > if (dev->alloc_ctx) > vb2_dma_contig_cleanup_ctx(dev->alloc_ctx); > v4l2_device_unregister(&dev->v4l2_dev); > @@ -3658,6 +3692,26 @@ static int coda_remove(struct platform_device *pdev) > return 0; > } > > +#ifdef CONFIG_PM_RUNTIME > +static int coda_runtime_resume(struct device *dev) > +{ > + struct coda_dev *cdev = dev_get_drvdata(dev); > + int ret = 0; > + > + if (dev->pm_domain) { > + ret = coda_hw_init(cdev); > + if (ret) > + v4l2_err(&cdev->v4l2_dev, "HW initialization failed\n"); > + } > + > + return ret; > +} > +#endif -- Regards, Sylwester -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html